Smithsonian Institute: great for looking at their exhibits and playing games

Colonial Williamsburg: take a closer look at the 18th century! There's also a kid's page with games and activities!

National Geographic for Kids: a great reference, but also has fun games and activities

Scholastic for Kids: also a great reference with games as learning tools

Time for Kids: keep up on the news!

Learn the States: practice knowing your states for our geography unit with this game

White House for Kids: learn about the executive branch on this site

Collection of Government Links: this site has a number of links to sites that will help you learn about the government!